Today, comScore and VivaKi announced a partnership that will provide ad viewability metrics for ads placed through the VivaKi Nerve Center’s Audience on Demand. ComScore’s validated Campaign Essentials will measure how often digital ads are actually viewed, rather than how often ads are served.

Anne Hunter, SVP of ad effectiveness for comScore, said the technology defines a viewable ad as one that displays at least 50 percent of its pixels on a user’s screen and remains there for at least one second.

“This is a partnership to enable the mass use of viewability in media buying decisions. It goes beyond measuring viewable impressions for a single campaign post facto to looking at viewability of large amounts of inventory in real time,” she said.

There’s a growing movement to measure viewability instead of impressions. Last fall, the Interactive Advertising Bureau called for the ad marketplace to move to the viewable impression standard, and in January, comScore released a report that found 31 percent of online ads purchased by 12 major brands were not viewable by the end user. An industry coalition wants the new metric to become a standard by the first quarter of 2013.

Last week, comScore announced that it had received accreditation from the Media Rating Council for its validated Campaign Essentials metrics, which measure viewability, brand safety, engagement, in-country geographic delivery, and remove of non-human traffic.

The new functionality will allow for campaign pre-optimization, according to Mike Zeman, VP, solutions, VivaKi Nerve Center. “The initial deployment of this new viewability metric has been reactionary: launch a campaign, understand which ads are performing well, then pulling the lever to optimize on that,” Zeman said.

“We’re trying to actually develop insights so we can become predictive and, from a pre-bid standpoint, factor viewability into inventory we’re willing to deploy our advertising on and into how much we’re willing to pay for those impressions.” VivaKi is Publicis Groupe’s digital agency network.

Zeman said his group has not asked permission of or notified publishers of its use of comScore’s viewability standard. “There are a lot of bad practices the industry has tolerated over the last 15 years, one of those being poor website design. So you have a lot of ad impressions that are not viewed today. This will force the hand of many publishers, in terms of cleaning things up,” he said.

VivaKi’s publisher and partner relations teams will work with publishers to give them insights on how they can improve viewability. “It’s not that a comScore 100 publisher will be cut from our white list and we won’t talk. There will be active dialog,” he said. He added that there are many publishers that are proactively working to increase ad viewability, notably MSNBC and ESPN.

And Hunter noted that Forbes.com is using comScore to provide viewable impression scores to clients.

“Good publishers tend to look good,” Hunter said. “Publishers need education about it as much as marketers. They want to understand how this affects their site. Once they understand that the implications are actually quite good for publishers that deliver good content, many great publishers are on board with it.”

Advertisers will need to opt in to use the measurement system. VivaKi’s brand relations team will explain the initiative to clients and encourage adoption, and Zeman expects most to sign on. He said, “We’ve had clients certainly actively cheer us on to do something like this.”

In more VivaKi news, yesterday Medialets announced it has become the mobile ad serving partner for VivaKi’s The Pool Tablet Lane in the United States. The Pool’s Tablet Lane is testing ad executions on tablet devices.

UPDATE: The story originally stated incorrectly that ComScore’s validated Campaign Essentials will be available to all advertisers using VivaKi’s Audience on Demand at no charge. They will not.